1. Field of the Invention
The invention generally relates to power-driven conveyors and to conveyors having a means to facilitate cleaning the conveyor or sterilizing means.
2. Description of the Prior Art
It is necessary to clean and sterilize the conveyor belt in the food processing industry as well as in other situations. A number of scrapers and wipers have been developed to do this job. It is desired to accomplish the best possible cleaning job, which often is judged by a bacteria count taken from the cleaned belt. Also, it is desired to accomplish the job by the easiest, least costly method.
A number of patents have disclosed methods and apparatus for cleaning conveyor belts. One is West German Patent No. 2,950,346, which shows a conveyor belt cleaner that includes a reservoir trough from which a cleaner belt picks up cleaning fluid and transfers it to the belt to be cleaned. The cleaner belt is moving in the opposite direction to the conveyor belt and simultaneously applies cleaning fluid and scours the conveyor belt. The cleaner belt is power-driven and appears to operate against the conveyor belt on a full time basis.
West German Patent No. 2,505,874 shows a cleaner for escalator handrails. The cleaning liquid is transferred to the handrail by application rollers, at least one of which rotates in a direction opposite to the handrail. Alternatively, an endless sponge or brush band applies the fluid while rotating oppositely to the handrail.
U.S. Pat. No. 3,946,853 to Ishida discloses a solution-bearing pad that is resiliently biased into contact with a moving belt in order to clean, polish, or disinfect an escalator handrail. The pad is secured by a C-shaped housing that is engaged over the sides of the handrail, and, apparently, the housing eventually rests against some fixed portion of the escalator so that the belt slides through the pad.
U.S. Pat. No. 3,941,241 to Hishitani discloses a similar escalator cleaning pad and housing, except that this housing is firmly connected to a fixed part of the escalator by a fastener.
Russian Patent No. 914,432 discloses a conveyor belt cleaning system in which an endless tape is sprayed with solvent and then moves against the dirty side of the belt as both belt and tape ride over a tape drum. Subsequently, the tape travels through a water tank and is pressed against a drying roller.
U.S. Pat. No. 1,543,411 to Wittig discloses a belt cleaner having a spray header that wets the belt. At a downstream location a rotating brush cleans the belt, while further downstream the knife scrapes the belt.
U.S. Pat. No. 4,344,361 to MacPhee et al. discloses a cleaner for a blanket cylinder. The cleaner advances a cloth sheet between a supply roll and a take-up roll. Between the two rolls, water and solvent are supplied to the cloth, and an inflatable bladder presses the cloth against the cylinder for cleaning.
Although these types of belt cleaners are known, it would be desirable to have a belt cleaner that need not be permanently installed on the belt, but rather could be applied when necessary and then removed to another area so that the belt cleaner could be cleaned and prepared for the next use.
Also, it would be desirable to have a suitable structure to enable the belt cleaner to be applied to substantially any conveyor belt without specially adapting the conveyor to receive the cleaner.
Another desirable feature is to have a belt cleaner that carries its own supply of cleaning solution so that the cleaner is not dependent upon the absorbency of the pad to handle the cleaning requirements of the entire belt.
Still another desirable feature is to have a belt cleaner that can quickly and inexpensively be cycled for repeated use.
To achieve the foregoing and other objects and in accordance with the purpose of the present invention, as embodied and broadly described herein, the conveyor belt cleaning apparatus and method of this invention may comprise the following.